The code coverage does not work in JDK 8. Some of the tests do not execute successfully in the instrumented JDK 8, thus reducing the accuracy of the coverage.

Here is an example stack trace of the failure:

[aginfra@sca00ivw WorkDir.CC]$ jtreg/bin/jtreg '-vmoptions:-Xms64m -Xmx728m' -verbose:default -compilejdk:ws/build/linux-amd64/jdk_orig -testjdk:ws/build/linux-amd64/jdk -ignore:quiet -timeout:2 -dir:ws/jdk/test/closed com/sun/corba/se/impl/io/InputStreamSubclassTest.java
Picked up JAVA_TOOL_OPTIONS: -Xms64m -Xmx4g
Picked up _JAVA_OPTIONS: -Xms64m -Xmx4g
Directory "JTwork" not found: creating
Directory "JTreport" not found: creating
Picked up JAVA_TOOL_OPTIONS: -Xms64m -Xmx4g
Picked up _JAVA_OPTIONS: -Xms64m -Xmx4g
runner starting test: closed/com/sun/corba/se/impl/io/InputStreamSubclassTest.java
runner finished test: closed/com/sun/corba/se/impl/io/InputStreamSubclassTest.java
Failed. Unexpected exit from test [exit code: 1]
Test results: failed: 1
 
Error occurred during initialization of VM
java.lang.ExceptionInInitializerError
        at java.lang.Class.checkPackageAccess(Class.java:2377)
        at java.lang.Class.checkMemberAccess(Class.java:2351)
        at java.lang.Class.getDeclaredField(Class.java:2070)
        at java.util.concurrent.atomic.AtomicReference.<clinit>(AtomicReference.java:57)
        at java.security.Policy.<clinit>(Policy.java:92)
        at java.security.AccessControlContext.getDebug(AccessControlContext.java:108)
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:399)
        at java.security.AccessController.checkPermission(AccessController.java:885)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
        at java.lang.SecurityManager.checkPropertyAccess(SecurityManager.java:1294)
        at java.lang.System.getProperty(System.java:717)
        at sun.misc.Launcher.<clinit>(Launcher.java:53)
        at java.lang.ClassLoader.initSystemClassLoader(ClassLoader.java:1451)
        at java.lang.ClassLoader.getSystemClassLoader(ClassLoader.java:1442)
Caused by: java.lang.NullPointerException
        at java.security.Policy.isSet(Policy.java:121)
        at java.security.AccessControlContext.getDebug(AccessControlContext.java:108)
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:399)
        at java.security.AccessController.checkPermission(AccessController.java:885)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
        at java.lang.SecurityManager.checkPropertyAccess(SecurityManager.java:1294)
        at java.lang.System.getProperty(System.java:717)
        at com.sun.tdk.jcov.runtime.PropertyFinder.findProperties(PropertyFinder.java:295)
        at com.sun.tdk.jcov.runtime.PropertyFinder.findValue(PropertyFinder.java:251)
        at com.sun.tdk.jcov.runtime.Collect.loadSaverExtension(Collect.java:260)
        at com.sun.tdk.jcov.runtime.Collect.init(Collect.java:311)
        at java.lang.reflect.Proxy.<clinit>(Proxy.java:425)
        at java.lang.Class.checkPackageAccess(Class.java:2377)
        at java.lang.Class.checkMemberAccess(Class.java:2351)
        at java.lang.Class.getDeclaredField(Class.java:2070)
        at java.util.concurrent.atomic.AtomicReference.<clinit>(AtomicReference.java:57)
        at java.security.Policy.<clinit>(Policy.java:92)
        at java.security.AccessControlContext.getDebug(AccessControlContext.java:108)
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:399)
        at java.security.AccessController.checkPermission(AccessController.java:885)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
        at java.lang.SecurityManager.checkPropertyAccess(SecurityManager.java:1294)
        at java.lang.System.getProperty(System.java:717)
        at sun.misc.Launcher.<clinit>(Launcher.java:53)
        at java.lang.ClassLoader.initSystemClassLoader(ClassLoader.java:1451)
        at java.lang.ClassLoader.getSystemClassLoader(ClassLoader.java:1442)